Progress of cyclodextrin based-membranes in water treatment: special 3D bowl-like structure to achieve excellent separation

Cyclodextrins (CDs) can achieve precise separation of molecules and ions at the same time as well as improve the permeability of the membranes due to their special cavity structure and amphipathic. This paper reviewed the application advantages and challenges of CD-based membranes in dye and salt separation, organic solvent nanofiltration, pollutants removal, etc in the past ten years, focusing on the design and fabrication methods of CD-based membranes and the improvement mechanisms of membrane performance. Understanding these mechanisms has important guiding significance for the design of CD-based membranes in the future. Finally, the future trend of CD-based membranes has been prospected. Although the properties of CDs for precise molecular recognition have achieved preliminary results, CDs did not significantly enhance the permeability of the membranes. Therefore, the directional arrangement of the CDs cavity and the cavity of CDs as the main mass transfer channel will greatly boost the selectivity and permeability of the membranes in future research.